CN114728843A

CN114728843A - Glass-based articles having fracture resistance stress profiles

Info

Publication number: CN114728843A
Application number: CN202080082828.XA
Authority: CN
Inventors: P·奥拉姆; R·V·鲁斯夫
Original assignee: Corning Inc
Current assignee: Corning Inc
Priority date: 2019-11-27
Filing date: 2020-11-12
Publication date: 2022-07-08
Also published as: TW202128586A; WO2021108138A1; US20210155533A1

Abstract

The glass-based article comprises a stress profile for providing improved fracture resistance and reduced weight gain. The glass-based article is produced using a single step ion exchange process.

Description

Glass-based articles having fracture resistance stress profiles

This application claims priority to U.S. provisional application serial No. 62/941,506 filed on 27.11/2019, the contents of which are hereby incorporated by reference in their entirety.

Background

Technical Field

The present description relates generally to stress profiles of fracture resistance stress profiles in glass-based articles. More particularly, the present description relates to stress profiles of glass-based articles that may contain lithium that may be used in electronic devices.

Background

The mobile nature of portable devices (e.g., smart phones, tablets, portable media players, personal computers, and cameras) makes these devices particularly susceptible to accidental falls on hard surfaces (e.g., the ground). These devices typically include cover glass that may be damaged after impact with a hard surface. In many of these devices, the cover glass acts as a display housing and may incorporate touch functionality, while the use of the device is negatively impacted when the cover glass is damaged.

There are two main modes of breakage of cover glass when an associated portable device is dropped onto a hard surface. One of the modes is flexural failure, which is caused by the glass bending when the device is subjected to dynamic loads impacting with a hard surface. Another mode is sharp contact breakage, which is caused by damage introduced to the glass surface. The impact of glass with rough hard surfaces (e.g., asphalt, granite, etc.) can result in sharp indentations in the glass surface. These indentations become sites of failure in the glass surface from which cracks may develop and propagate.

Glass manufacturers and handheld device manufacturers are continually striving to improve the resistance of handheld devices to breakage. Portable devices are also desired to be as thin as possible. Therefore, in addition to strength, it is also desirable that the glass as the cover glass in the portable device be as thin as possible. Thus, in addition to increasing the strength of the cover glass, it is also desirable for the glass to have mechanical properties that allow for formation by processes that enable the manufacture of thin glass articles (e.g., thin glass sheets).

Thus, there is a need for a glass-based article that can be strengthened (e.g., by ion exchange strengthening) and has mechanical properties that allow the glass-based article to be formed as a thin article.

Disclosure of Invention

According to aspects(1) A glass-based article is provided. The glass-based article comprises: a first surface and a second surface defining a thickness t, wherein t is greater than or equal to 0.2mm and less than or equal to 2.0 mm; a peak tension PT of greater than or equal to 21 MPa; a compressive stress CS of 650MPa or more and 1200MPa or less; a peak depth of layer DOL of greater than or equal to 4.5 μm and less than or equal to 12.0 μm_SP(ii) a And an inflection point compressive stress CS of 15MPa or more and 150MPa or less_K。

According to aspect (2), there is provided the glass-based article of aspect (1), wherein the glass-based article is formed using a single ion exchange process.

According to aspect (3), there is provided the glass-based article of any one of aspects (1) to (d) above, wherein PT is less than or equal to 80 MPa.

According to aspect (4), there is provided the glass-based article of any one of aspects (1) to (d) above, wherein PT is greater than or equal to 43MPa and less than or equal to 78 MPa.

According to aspect (5), there is provided the glass-based article of any one of aspects (1) to (d) above, wherein CS is greater than or equal to 800MPa and less than or equal to 1050 MPa.

According to aspect (6), there is provided the glass-based article of any one of aspects (1) to (1) above, wherein DOL_SPGreater than or equal to 6.0 μm and less than or equal to 11.5. mu.m.

According to aspect (7), there is provided the glass-based article of any one of aspects (1) to (1) above, wherein CS_KGreater than or equal to 30MPa and less than or equal to 125 MPa.

According to aspect (8), there is provided the glass-based article of any one of aspects (1) to (d) above, wherein DOL_SPAnd/t is 0.010 or more and 0.030 or less.

According to aspect (9), there is provided the glass-based article of any one of aspects (1) to (d) above, further comprising a depth of compression DOC, wherein DOC is greater than or equal to 0.11 t.

According to aspect (10), there is provided the glass-based article of any one of aspects (1) to (1) above, further comprising a stress-depth integral a in the tensile stressed region, and a/(PT) is greater than or equal to 0.4.

According to aspect (11), there is provided the glass-based article of any one of aspects (1) to (d) above, further comprising a stress-depth integral a in the tensile stressed region, and a/(PT) is less than or equal to 0.71.

According to aspect (12), there is provided the glass-based article of any one of aspects (1) to (d) above, further comprising a stress-depth integral, a, in the tensile stressed region, and a/t is greater than or equal to 16 MPa.

According to aspect (13), there is provided the glass-based article of any one of aspects (1) through the preceding aspects, further comprising a stress-depth integral a in the tensile stressed region, and a/t is less than or equal to 22 MPa.

According to aspect (14), there is provided the glass-based article of any one of aspects (1) to (1) above, further comprising a stress-depth integral a in the tensile stressed region, and a/t^3/2Greater than or equal to 24MPa/mm^1/2。

According to aspect (15), there is provided the glass-based article of any one of aspects (1) to (1) above, further comprising a stress-depth integral a in the tensile stressed region, and a/t^3/2Less than or equal to 43MPa/mm^1/2。

According to aspect (16), there is provided the glass-based article of any one of aspects (1) to (1) above, wherein PT/(ett) is less than or equal to 2.2m^-1And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

According to aspect (17), there is provided the glass-based article of any one of aspects (1) to (1) above, wherein PT/(E t) is greater than or equal to 0.8m^-1And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

According to aspect (18), there is provided the glass-based article of any one of aspects (1) to (1) above, further comprising a stress-depth integral a in the tensile stressed region, and a/(E t) is less than or equal to 9 x 10^-4And E is a group having the same center as the glass-based articleThe Young's modulus of the microstructured glass-based substrate.

According to aspect (19), there is provided the glass-based article of any one of aspects (1) to (d) above, further comprising a stress-depth integral a in the tensile stressed region, and a/(E t) is greater than or equal to 3.5 x 10^-4And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

According to aspect (20), there is provided the glass-based article of any one of aspects (1) to (1) above, wherein t is less than or equal to 0.65mm and PT is less than or equal to 60 MPa.

According to aspect (21), there is provided the glass-based article of any one of aspects (1) to (d) above, wherein t is greater than or equal to 0.3mm and less than or equal to 0.8 mm.

According to aspect (22), there is provided the glass-based article of any one of aspects (1) to (d) above, wherein t is greater than or equal to 0.4mm and less than or equal to 0.6 mm.

According to aspect (23), there is provided the glass-based article of any one of aspects (1) to (d) above, wherein Li at the center of the glass-based article₂Molar concentration of O and Na₂The ratio of the molar concentration of O is less than or equal to 2.0.

According to aspect (24), there is provided the glass-based article of any one of aspects (1) to (d) above, wherein Li at the center of the glass-based article₂The O concentration is less than or equal to 12 mol%.

According to aspect (25), a glass-based article is provided. The glass-based article comprises: a first surface and a second surface defining a thickness t, wherein t is greater than or equal to 0.2mm and less than or equal to 2.0 mm; a peak tension PT of greater than or equal to 21 MPa; a compressive stress CS of 650MPa or more and 1200MPa or less; peak depth of layer DOL_SPWherein DOL_SPThe/t is greater than or equal to 0.007 and less than or equal to 0.030; and an inflection point compressive stress CS of 15MPa or more and 150MPa or less_K。

According to aspect (26), there is provided the glass-based article of aspect (25), wherein the glass-based article is formed using a single ion exchange process.

According to aspect (27), there is provided the glass-based article of any one of aspects (25) to (d) above, wherein PT is less than or equal to 80 MPa.

According to aspect (28), there is provided the glass-based article of any one of aspects (25) to (d) above, wherein PT is greater than or equal to 43MPa and less than or equal to 78 MPa.

According to aspect (29), there is provided the glass-based article of any one of aspects (25) to (i) above, wherein CS is greater than or equal to 800MPa and less than or equal to 1050 MPa.

According to aspect (30), there is provided the glass-based article of any one of aspects (25) to the preceding aspects, wherein DOL_SPGreater than or equal to 6.0 μm and less than or equal to 11.5. mu.m.

According to aspect (31), there is provided the glass-based article of any one of aspects (25) to the preceding aspect, wherein CS_KGreater than or equal to 30MPa and less than or equal to 125 MPa.

According to aspect (32), there is provided the glass-based article of any one of aspects (25) to the preceding aspect, wherein DOL_SPThe/t is 0.010 or more and 0.029 or less.

According to aspect (33), there is provided the glass-based article of any one of aspects (25) to the preceding aspect, further comprising a depth of compression DOC, wherein DOC is greater than or equal to 0.11 t.

According to aspect (34), there is provided the glass-based article of any one of aspects (25) to (i) the preceding aspect, further comprising a stress-depth integral a in the tensile stressed region, and a/(PT) is greater than or equal to 0.4.

According to aspect (35), there is provided the glass-based article of any one of aspects (25) to the preceding aspects, further comprising a stress-depth integral a in the tensile stressed region, and a/(PT) is less than or equal to 0.71.

According to aspect (36), there is provided the glass-based article of any one of aspects (25) to (d) the preceding aspect, further comprising a stress-depth integral, a, in the tensile stress region, and a/t is greater than or equal to 16 MPa.

According to aspect (37), there is provided the glass-based article of any one of aspects (25) to the preceding aspect, further comprising a stress-depth integral, a, in the tensile stress region, and a/t is less than or equal to 22 MPa.

According to aspect (38), there is provided the glass-based article of any one of aspects (25) to the preceding aspect, further comprising a stress-depth integral a in the tensile stress region, and a/t^3/2Greater than or equal to 24MPa/mm^1/2。

According to aspect (39), there is provided the glass-based article of any one of aspects (25) to the preceding aspect, further comprising a stress-depth integral a in the tensile stress region, and a/t^3/2Less than or equal to 43MPa/mm^1/2。

According to aspect (40), there is provided the glass-based article of any one of aspects (25) to (i) above, wherein PT/(E t) is less than or equal to 2.2m^-1And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

According to aspect (41), there is provided the glass-based article of any one of aspects (25) to (d) above, wherein PT/(E t) is greater than or equal to 0.8m^-1And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

According to aspect (42), there is provided the glass-based article of any one of aspects (25) to (d) the preceding aspect, further comprising a stress-depth integral a in the tensile stressed region, and a/(E t) is less than or equal to 9 x 10^-4And E is the young's modulus of a glass-based substrate having the same composition and microstructure as the center of the glass-based article.

According to aspect (43), there is provided the glass-based article of any one of aspects (25) to the preceding aspect, further comprising a stress-depth integral a in the tensile stressed region, and a/(E t) is greater than or equal to 3.5 x 10^-4And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

According to aspect (44), there is provided the glass-based article of any one of aspects (25) to (i) above, wherein t is less than or equal to 0.65mm and PT is less than or equal to 60 MPa.

According to aspect (45), there is provided the glass-based article of any one of aspects (25) to (i) above, wherein t is greater than or equal to 0.3mm and less than or equal to 0.8 mm.

According to aspect (46), there is provided the glass-based article of any one of aspects (25) to (d) above, wherein t is greater than or equal to 0.4mm and less than or equal to 0.6 mm.

According to aspect (47), there is provided the glass-based article of any one of aspects (25) to the preceding aspect, wherein Li at the center of the glass-based article₂Molar concentration of O and Na₂The ratio of the molar concentration of O is less than or equal to 2.0.

According to aspect (48), there is provided the glass-based article of any one of aspects (25) to (i) above, wherein Li at the center of the glass-based article₂The O concentration is less than or equal to 12 mol%.

According to aspect (49), a consumer electronic product is provided. The consumer electronic product comprises: a housing comprising a front surface, a rear surface, and side surfaces; an electrical component disposed at least partially within the housing, the electrical component including at least a controller, a memory, and a display, the display disposed at or adjacent to a front surface of the housing; and the outer cover is arranged above the display. At least a portion of at least one of the housing and the enclosure comprises a glass-based article of any of the preceding aspects.

According to aspect (50), a method is provided. The method comprises the following steps: the glass-based substrate is exposed to an ion exchange bath to form a glass-based article. The glass-based substrate includes a first surface and a second surface defining a thickness t, where t is greater than or equal to 0.2mm and less than or equal to 2.0 mm. The glass-based article comprises: a peak tension PT of greater than or equal to 21 MPa; a compressive stress CS of 650MPa or more and 1200MPa or less; a peak depth of layer DOL of greater than or equal to 4.5 μm and less than or equal to 12.0 μm_SP(ii) a And an inflection point compressive stress CS of 15MPa or more and 150MPa or less_K(ii) a And the ion exchange bath comprises potassium and sodium.

According to an aspect (51), there is provided a methodA method. The method comprises the following steps: the glass-based substrate is exposed to an ion exchange bath to form a glass-based article. The glass-based substrate comprises: a first surface and a second surface defining a thickness t, wherein t is greater than or equal to 0.2mm to less than or equal to 2.0 mm. The glass-based article comprises: a peak tension PT of greater than or equal to 21 MPa; a compressive stress CS of 650MPa or more and 1200MPa or less; peak depth of layer DOL_SPWherein DOL_SPT is greater than or equal to 0.007 and less than or equal to 0.030; and an inflection point compressive stress CS of 15MPa or more and 150MPa or less_K(ii) a And the ion exchange bath comprises potassium and sodium.

According to aspect (52), there is provided the method of any one of aspects (50) to (d) above, wherein the method does not comprise any additional ion exchange treatment.

According to aspect (53), there is provided the method of any one of aspects (50) to the preceding aspects, wherein the temperature of the ion exchange bath is greater than or equal to 370 ℃ and less than or equal to 450 ℃.

According to aspect (54), there is provided the method of any one of aspects (50) to the preceding aspects, wherein the temperature of the ion exchange bath is greater than or equal to 380 ℃ and less than or equal to 420 ℃.

According to aspect (55), there is provided the method of any one of aspects (50) to the preceding aspects, wherein the temperature of the ion exchange bath is greater than or equal to 380 ℃ and less than or equal to 390 ℃.

According to aspect (56), there is provided the method of any one of aspects (50) to the preceding aspects, wherein the ion exchange bath comprises NaNO₃The amount of (b) is greater than or equal to 1 wt% and less than or equal to 10 wt%.

According to aspect (57), there is provided the method of any one of aspects (50) to the preceding aspects, wherein the ion exchange bath comprises NaNO₃The amount of (b) is greater than or equal to 4 wt% and less than or equal to 9 wt%.

According to aspect (58), there is provided the method of any one of aspects (50) to the preceding aspects, wherein the exposing is for a time greater than or equal to 15 minutes and less than or equal to 200 minutes.

According to aspect (59), there is provided the method of any one of aspects (50) to the preceding aspects, wherein the exposing is for a time greater than or equal to 65 minutes and less than or equal to 180 minutes.

According to aspect (60), there is provided the method of any one of aspects (50) to (1), wherein the glass-based substrate comprises Li₂Molar concentration of O and Na₂The ratio of the molar concentration of O is less than or equal to 2.0.

According to aspect (61), there is provided the method of any one of aspects (50) to the preceding aspects, wherein the glass-based substrate comprises Li₂The O concentration is less than or equal to 12 mol%.

According to aspect (62), there is provided the method of any one of aspects (50) to the previous aspects, wherein the weight gain of the glass-based article is less than or equal to 1% compared to the glass-based substrate.

Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments described herein and together with the description serve to explain the principles and operations of the claimed subject matter.

Drawings

FIG. 1 is a schematic illustration of a stress profile including inflection point stresses;

FIG. 2 schematically illustrates a cross-section of a glass having a compressive stress layer on a surface thereof according to embodiments described and illustrated herein;

fig. 3A is a plan view of an exemplary electronic device comprising any of the glass articles disclosed herein;

FIG. 3B is a perspective view of the exemplary electronic device of FIG. 3A;

FIG. 4 is a stress profile of an embodiment glass-based article and a comparative glass-based article;

FIG. 5 is a stress profile of a glass-based article according to an embodiment versus a comparative glass-based article;

FIG. 6 is a delay curve of a glass-based article according to an embodiment;

FIG. 7 is a selected portion of the delay profile of FIG. 6; and

fig. 8 is a linear fit of the central portion of the delay curve of fig. 6.

Detailed Description

Before describing several exemplary embodiments, it is to be understood that the disclosure is not limited to the details of construction or process steps set forth in the following disclosure. The disclosure provided herein is capable of other embodiments and of being practiced or of being carried out in various ways.

Reference in the specification to "one embodiment," "certain embodiments," "various embodiments," "one or more embodiments," or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of the phrases "in one or more embodiments," "in certain embodiments," "in various embodiments," "in one embodiment," or "in an embodiment" in various places throughout this specification are not necessarily referring to the same embodiment, or to only one embodiment. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

Defining and measuring techniques

The terms "glass-based article" and "glass-based substrate" are used to include any object made in whole or in part of glass, including glass-ceramics (including amorphous and crystalline phases). Generally, glass-based substrates are subjected to an ion exchange treatment to form a glass-based article. Laminated glass-based articles include laminates of glass materials, laminates of glass and non-glass materials, and/or laminates of glass and crystalline materials. The glass-based substrate according to one or more embodiments may be selected from the group consisting of soda lime silicate glass, alkali aluminosilicate glass, alkali-containing borosilicate glass, alkali-containing aluminoborosilicate glass, and alkali-containing glass-ceramics.

The "base composition" is the chemical composition of the substrate prior to any ion exchange (IOX) treatment. That is, the base composition is not doped with any ions from the IOX. In other words, the glass-based substrate has a base composition prior to being subjected to the ion exchange treatment. The center of the IOX-treated glass-based article is minimally affected by IOX treatment and may not be affected by IOX treatment. For this reason, the composition at the center of the glass-based article may be the same as the base composition when the IOX treatment conditions are such that ions supplied to the IOX do not diffuse into the center of the substrate. In one or more embodiments, the center composition at the center of the glass article includes a base composition. In addition, a glass-based substrate having the same composition and microstructure as the center of the glass-based article may have equivalent properties to the substrate used to form the glass-based article.

It should be noted that the terms "substantially" and "about" may be used herein to represent the degree of inherent uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. The use of these terms herein to represent a quantitative representation may vary from the stated reference without resulting in a change in the basic function of the subject matter at issue. Thus, for example, a glass-based article that is "substantially free of MgO" means that no MgO is actively added or dosed to the glass-based article, but that it may be present in very small amounts as a contaminant. As used herein, the term "about" means that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact, but may be approximate and/or larger or smaller as desired, such as to reflect tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art. When the term "about" is used to describe a numerical value or an end-point of a range, this disclosure should be understood to include the specific numerical value or end-point referred to. Whether or not the numerical values or endpoints of ranges in the specification are listed as "about," the numerical values or endpoints of ranges are intended to include both embodiments: one modified with "about" and the other not modified with "about". It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

All compositions described herein are expressed in mole percent (mol%) on an oxide basis unless otherwise indicated.

The "stress profile" is the stress as a function of depth through the thickness of the glass-based article. The compressive stress region extends from a first surface of the article to a depth of compression (DOC), where the article is under compressive stress. The central tension region extends from the DOC to include a region of the article under tensile stress. In other words, the first compressive stress region may extend from the first surface to a first depth of compression (DOC)₁) Drawing zone from DOC₁Extending to a second depth of compression (DOC)₂) Second compression zone from DOC₂Extending to the second surface. In embodiments where the stress profile is symmetrical, the distance from each surface to the respective DOCs is equal.

As used herein, depth of compression (DOC) refers to the depth at which the stress within the glass-based article changes from compressive to tensile. At the DOC, the stress crosses from positive (compressive) to negative (tensile) and thus assumes a zero stress value. According to the convention commonly used in the field of mechanics, compression is denoted as negative (< 0) stress, while tension is denoted as positive (> 0) stress. However, throughout this specification, a positive value of stress is Compressive Stress (CS), which is expressed as a positive or absolute value (i.e., CS ═ CS |, as described herein). In addition, the negative value of the stress is tensile stress. But using the term "tensile", stress or Central Tension (CT) may be expressed as a positive value (i.e., CT | CT |). Central Tension (CT) refers to the tensile stress in the central region or central tension region of the glass-based article. The maximum central tension occurs in the central tension region at nominally 0.5-t (where t is the article thickness), which allows for precise central deviation from the location of maximum tensile stress. Peak Tension (PT) refers to the maximum tension measured and may or may not be at the center of the article.

The "knee" of a stress profile is the depth of the article at which the slope of the stress profile transitions from steep to flat. The steep portion of the stress profile extending from the surface into the glass-based article is referred to as a "spike". An inflection point may refer to a transition region within the span of depths at which the slope changes. Knee compressive stress CS_KDepth DOL defined as the extrapolation of the deeper portion of the CS profile to the peak_SPThe value of the compressive stress at (a). DOL_SPReported as measured by known methods using a surface strain gauge. Fig. 1 provides a schematic illustration of a stress profile including inflection point stress.

The non-zero metal oxide concentration for the metal oxide that varies from the first surface to the depth of layer or along at least a majority of the article thickness (t) indicates that stress has been generated in the article due to ion exchange. The change in metal oxide concentration may be referred to herein as a metal oxide concentration gradient. A metal oxide that is not zero in concentration and that varies from the first surface to the depth of layer or along a portion of the thickness may be described as creating a stress in the glass-based article. A concentration gradient or change in the metal oxide is created by chemically strengthening the glass-based substrate, wherein a plurality of first metal ions in the glass-based substrate are exchanged with a plurality of second metal ions.

Unless otherwise indicated, CT and CS are expressed herein in megapascals (MPa), thickness in millimeters, and DOC and DOL in micrometers (μm).

Compressive stress (including peak values CS, CS)_{Maximum of}) And DOL_SPMeasured by a surface stress meter (FSM) using a commercially available instrument such as FSM-6000 manufactured by Orihara Industrial Co., Ltd. (Japan). Surface stress measurements depend on the accurate measurement of stress optical number (SOC) related to the birefringence of the glass. Then, according to the title "Standard Test Method for Measurement of Glass Stress-OpticalSOC was measured by procedure C (glass plate method) as described in ASTM Standard C770-16 of Coefficient, "the contents of which are incorporated herein by reference in their entirety. The surface stress meter measurements reported herein are provided at a measurement wavelength where the fractional part of the fringe count for two fringes ranges from 0.1 to 0.8, preferably from 0.15 to 0.7, as much as possible.

The Central Tension (CT) and Peak Tension (PT) and stress hold values were measured using scattered light polarizer (scapp) techniques known in the art. A Refracted Near Field (RNF) method or SCALP may be used to measure the stress profile versus depth of compression (DOC). When the RNF method is used to measure the stress distribution curve, the maximum CT value provided by SCALP is used in the RNF method. Specifically, the RNF measured stress profile is force balanced and calibrated to the maximum CT value provided by the scapp measurement. The RNF method is described in U.S. Pat. No. 8,854,623 entitled "Systems and methods for measuring a profile characterization of a glass sample," which is incorporated herein by reference in its entirety. Specifically, the RNF method includes placing a glass article adjacent to a reference block, generating a polarization-switched light beam that is switched between orthogonal polarizations at a frequency of 1Hz to 50Hz, measuring an amount of power in the polarization-switched light beam, and generating a polarization-switched reference signal, wherein the amounts of power measured in each of the orthogonal polarizations are within 50% of each other. The method further comprises the following steps: the polarization-switched beam is transmitted through the glass sample and the reference block to different depths into the glass sample, and the transmitted polarization-switched beam is then relayed to a signal optical detector using a relay optical system, where the signal optical detector generates a polarization-switched detector signal. The method further comprises the following steps: the detector signal is divided by the reference signal to form a normalized detector number, and the profile characteristic of the glass sample is determined from the normalized detector signal.

The Young's modulus value index described in this disclosure is the value measured by a resonance ultrasonic Spectroscopy technique of the general type set forth in ASTM E2001-13 entitled "Standard Guide for reactive ultra Spectroscopy for Defect Detection in Box Metallic and Non-Metallic Parts".

Glass baseSummary of the Properties of the article

The glass-based articles herein have a stress profile designed to increase the probability of integrity after multiple drops onto a hard surface. When combined with these favorable stress profiles, high fracture toughness provides a new, higher level of fracture resistance. Stress profiles and methods for forming glass-based articles are selected to minimize weight gain during the ion exchange process. The warpage generated by IOX treatment increases with increasing weight gain. Thus, the glass-based articles and stress profiles described herein are particularly useful in applications where warpage is a problem. Warping is particularly problematic for articles having low thickness, especially less than about 0.6mm thickness, articles having complex shapes (e.g., watch housings or 3D electronic device housings and housings) and/or when the articles are large (e.g., tablet or laptop screen housings). In addition, excessive warpage may prevent the article from forming a hermetic seal, which is becoming increasingly important in watch and consumer electronic device applications.

The glass-based substrate used to form the glass-based articles having the stress profiles described herein may be formed from any suitable material, for example, an alkali aluminosilicate glass. Alkali aluminosilicate glasses have good ion exchange properties, and chemical strengthening has been used to achieve high strength and high toughness properties in alkali aluminosilicate glasses. Soda-aluminosilicate glasses are highly ion-exchangeable glasses having high glass formability and quality. Lithium aluminosilicate glasses are highly ion exchangeable glasses with a high glass quality. Mixing Al₂O₃The substitution into the silicate glass network increases the mutual diffusivity of the monovalent cations during ion exchange. By applying a molten salt bath (e.g., KNO)₃And/or NaNO₃) The chemical strengthening in (2) can realize the glass with high strength, high toughness and high indentation and crack resistance. The shape of the stress profile obtained by chemical strengthening can affect drop performance, strength, toughness, and other attributes of the glass-based article.

Lithium aluminosilicate glasses are particularly desirable for use in the formation of chemically strengthened glass-based articles because they provide good physical properties, chemical durability, and ion-exchangeable properties. Greater Peak Tension (PT), depth of compression (DOC), and Compressive Stress (CS) may be achieved through different ion exchange processes. The stress profiles described herein provide increased fracture resistance and may be preferably applied to lithium-containing glass-based articles.

In embodiments of the compositions described herein, the constituent (e.g., SiO)₂、Al₂O₃、Li₂O, and the like) are given in mole percent (mol%) on an oxide basis unless otherwise specified. It is to be understood that any of the various stated ranges for one ingredient may be combined separately with any of the various stated ranges for any of the other ingredients.

The stress profile disclosed herein exhibits increased fracture resistance, which can be characterized by improved performance in drop tests. Referring to fig. 2, the glass-based article has a first region under compressive stress (e.g., the first compressive stress layer 120 and the second compressive stress layer 122 of fig. 2) extending from the surface to a depth of compression (DOC) of the glass and a second region under tensile stress or Central Tension (CT) (e.g., the central region 130 of fig. 2) extending from the DOC to a central or interior region of the glass.

The Compressive Stress (CS) has a maximum or peak that typically occurs at the surface of the glass-based article [ although this need not be the case, as the peak may occur at some depth from the surface of the glass-based article (e.g., near the surface of the glass)]Whereas CS varies as a function of the distance d from the surface. Referring again to FIG. 2, a first layer 120 of compressive stress extends from the first surface 110 to a depth d₁And a second layer 122 of compressive stress extends from the second surface 112 to a depth d₂. Together, these sections define the compression or CS of the glass-based article 100.

The compressive stresses of the two major surfaces 110, 112 in fig. 2 are balanced by the stored tension in the central region 130 of the glass-based article.

As described hereinThe glass-based article of (a) has a non-zero concentration of alkali metal oxide present, with the non-zero concentration in terms of metal oxide varying between a depth of layer (DOL) and one or both of the first and second surfaces. A stress profile is generated due to the non-zero concentration of the metal oxide that varies from the first surface. The non-zero concentration may vary along a portion of the thickness of the article. In some embodiments, the concentration of alkali metal oxide is not zero and varies along a thickness range of about 0-t to about 0.3-t. In some embodiments, the concentration of alkali metal oxide is not zero and varies along a thickness range of about 0-t to about 0.35-t, about 0-t to about 0.4-t, about 0-t to about 0.45-t, about 0-t to about 0.48-t, or about 0-t to about 0.50-t. The concentration of alkali metal oxide may include more than one metal oxide (e.g., Na)₂O and K₂A combination of O). In some embodiments, in the case where two metal oxides are used and the radii of the ions are different from each other, at a shallow depth, the concentration of the ions having a larger radius is greater than that of the ions having a smaller radius, and at a deeper depth, the concentration of the ions having a smaller radius is greater than that of the ions having a larger radius.

In an embodiment, the glass-based article comprises a Peak Tension (PT) greater than or equal to 21MPa, e.g., greater than or equal to 25MPa, greater than or equal to 30MPa, greater than or equal to 40MPa, greater than or equal to 43MPa, greater than or equal to 45MPa, greater than or equal to 50MPa, greater than or equal to 55MPa, greater than or equal to 60MPa, greater than or equal to 70MPa, or more. In an embodiment, the glass-based article has a PT of less than or equal to 80MPa, e.g., less than or equal to 78MPa, less than or equal to 75MPa, less than or equal to 70MPa, less than or equal to 65MPa, less than or equal to 60MPa, less than or equal to 55MPa, less than or equal to 50MPa, less than or equal to 45MPa, less than or equal to 40MPa, less than or equal to 35MPa, less than or equal to 30MPa, less than or equal to 25MPa, or less. PT may fall within a range formed between any of the foregoing values. In embodiments, the glass-based article comprises a Peak Tension (PT) in a range from greater than or equal to 21MPa to less than or equal to 80MPa, e.g., greater than or equal to 25MPa to less than or equal to 75MPa, greater than or equal to 30MPa to less than or equal to 70MPa, greater than or equal to 35MPa to less than or equal to 65MPa, greater than or equal to 40MPa to less than or equal to 60MPa, greater than or equal to 45MPa to less than or equal to 55MPa, greater than or equal to 43MPa to less than or equal to 78MPa, and any range or subrange formed between the foregoing endpoints. PT correlates with the amount of compressive stress introduced into the glass-based article by the ion exchange treatment. Thus, a higher PT value may indicate that more compressive stress has been applied to the glass-based article, while greater fracture resistance may be permitted. If the PT value is too high, the glass-based article may become brittle, which is undesirable for many applications. Further, if the glass-based article is thin, which increases the likelihood of IOX induced warpage, the upper PT limit may be selected to avoid excessive warpage and may be significantly lower than the PT associated with transition to brittle behavior. In an embodiment, the glass-based article having a thickness of less than or equal to 0.65mm has a PT of less than or equal to 60MPa, e.g., less than or equal to 55MPa, or less.

In one or more embodiments, the glass-based article comprises a peak Compressive Stress (CS) in a range from greater than or equal to 650MPa to less than or equal to 1200MPa, e.g., greater than or equal to 700MPa to less than or equal to 1150MPa, greater than or equal to 750MPa to less than or equal to 1100MPa, greater than or equal to 800MPa to less than or equal to 1050MPa, greater than or equal to 850MPa to less than or equal to 1000MPa, greater than or equal to 900MPa to less than or equal to 950MPa, greater than or equal to 800MPa to less than or equal to 1050MPa, and all ranges and subranges formed between any of the foregoing endpoints. The peak compressive stress may be located at or near a surface of the glass-based article.

In an embodiment, the glass-based article comprises a knee Compressive Stress (CS)_K) Ranging from greater than or equal to 15MPa to less than or equal to 150MPa, for example, greater than or equal to 30MPa to less than or equal to 125MPa, greater than or equal to 20MPa to less than or equal to 145MPa, greater than or equal to 25MPa to less than or equal to 140MPa, greater than or equal to 30MPa to less than or equal to 135MPa, greater than or equal to 35MPa to less than or equal to 130MPa, greater than or equal toFrom 40MPa or more to 125MPa or less, from 45MPa or more to 120MPa or less, from 50MPa or more to 115MPa or less, from 55MPa or more to 110MPa or less, from 60MPa or more to 105MPa or less, from 65MPa or more to 100MPa or less, from 70MPa or more to 95MPa or less, from 75MPa or more to 90MPa or less, from 85MPa or more to 85MPa or less, and all ranges and subranges formed between any of the foregoing endpoints. High level of CS_KAssociated with fractures caused by mechanisms that prevent bending of the glass-based article (e.g., having an experience of falling onto a rough surface) simultaneous with or subsequent to the introduction of the sharp damage.

In embodiments, the glass-based article comprises a depth of compression (DOC) of greater than or equal to 0.11t, where t is the thickness of the glass-based article, e.g., a depth of compression of greater than or equal to 0.12t, greater than or equal to 0.13t, greater than or equal to 0.14t, greater than or equal to 0.15t, greater than or equal to 0.16t, greater than or equal to 0.17t, greater than or equal to 0.18t, greater than or equal to 0.19t, greater than or equal to 0.20t, greater than or equal to 0.21t, greater than or equal to 0.22t, greater than or equal to 0.23t, or more. In embodiments, the DOC is less than or equal to 0.30t, e.g., less than or equal to 0.29t, less than or equal to 0.28t, less than or equal to 0.27t, less than or equal to 0.26t, less than or equal to 0.25t, less than or equal to 0.24t, or less, where t is the thickness of the glass-based article. The DOC can fall within a range formed between any of the foregoing values.

In one or more embodiments, the glass-based article comprises a depth of spike layer (DOL)_SP) The peak depth of layer ranges from greater than or equal to 4.5 μm to less than or equal to 12.0 μm, e.g., greater than or equal to 5.0 μm to less than or equal to 11.5 μm, greater than or equal to 5.5 μm to less than or equal to 11.0 μm, greater than or equal to 6.0 μm to less than or equal to 10.5 μm, greater than or equal to 6.5 μm to less than or equal to 10.0 μm, greater than or equal to 7.0 μm to less than or equal to 9.5 μm, greater than or equal to 7.5 μm to less than or equal to 9.0 μm, greater than or equal to 8.0 μm to less than or equal to 8.5 μm, greater than or equal to 6.0μ m to less than or equal to 11.5 μm, and all ranges and subranges formed between any of the foregoing endpoints. DOL_SPMay fall within a range formed between any of the preceding values. In an embodiment, DOL_SPT is greater than or equal to 0.007 to less than or equal to 0.030, e.g., greater than or equal to 0.010 to less than or equal to 0.030, greater than or equal to 0.010 to less than or equal to 0.029, greater than or equal to 0.015 to less than or equal to 0.025, greater than or equal to 0.020 to less than or equal to 0.030, and all ranges and subranges formed between any of the foregoing endpoints, wherein t is the thickness of the glass-based article.

The stress profile of the glass-based articles described herein may be characterized by a stress-depth integral (a), more specifically a ratio a/(PT). In embodiments, the ratio a/(PT t) is greater than or equal to 0.4, e.g., greater than or equal to 0.45, greater than or equal to 0.5, greater than or equal to 0.55, greater than or equal to 0.6, greater than or equal to 0.65, greater than or equal to 0.7, or more. In embodiments, the ratio a/(PT) is less than or equal to 0.75, e.g., less than or equal to 0.71, less than or equal to 0.7, less than or equal to 0.65, less than or equal to 0.6, less than or equal to 0.55, less than or equal to 0.5, less than or equal to 0.45, or less. In embodiments, the ratio a/(PT) ranges from greater than or equal to 0.4 to less than or equal to 0.71, e.g., greater than or equal to 0.45 to less than or equal to 0.70, greater than or equal to 0.5 to less than or equal to 0.65, greater than or equal to 0.55 to less than or equal to 0.6, and all ranges and subranges formed between any of the foregoing endpoints. If the ratio (a/PT × t) is too low, the compression depth may become undesirably shallow. The ratio a/(PT) can be determined by measuring the full phase shift of the retardation curve produced by the stress profile in a diffuse light polarizer (e.g., commercial instruments SLP-1000 and SLP-2000 produced by Orihara). The peak tension is equal to the maximum slope occurring between the minimum and maximum delays of the smoothed delay curve. The minimum and maximum values occur at two locations (e.g., at two depths of compression) where the stress in the glass-based article changes from compressive stress to tensile. The ratio a/(PT) is taken when the total change in retardation from minimum to maximum is divided by the maximum slope and by the thickness. The slope is measured relative to the thickness dimension, e.g., the slope is a derivative of the delay relative to a spatial coordinate along the thickness dimension. The range of ratios a/(PT x t) described herein ensures a stress profile produced by the IOX treatment protocol in which the weight gain of the glass is approximately linearly related to strengthening, and ultimately the weight gain continues to increase approximately linearly as the rate of increase of the strengthening characteristic decreases during the IOX treatment.

The stress profile of the glass-based articles described herein may be characterized by a ratio a/t. In embodiments, the ratio A/t is greater than or equal to 16MPa, e.g., greater than or equal to 17MPa, greater than or equal to 18MPa, greater than or equal to 19MPa, greater than or equal to 20MPa, greater than or equal to 21MPa, greater than or equal to 22MPa, greater than or equal to 23MPa, greater than or equal to 24MPa, greater than or equal to 25MPa, greater than or equal to 26MPa, greater than or equal to 27MPa, greater than or equal to 28MPa, greater than or equal to 29MPa, greater than or equal to 30MPa, greater than or equal to 31MPa, greater than or equal to 32MPa, or more. In embodiments, the ratio A/t is less than or equal to 33MPa, e.g., less than or equal to 32MPa, less than or equal to 31MPa, less than or equal to 30MPa, less than or equal to 29MPa, less than or equal to 28MPa, less than or equal to 27MPa, less than or equal to 26MPa, less than or equal to 25MPa, less than or equal to 24MPa, less than or equal to 23MPa, or less. In embodiments, the range of ratio a/t is greater than or equal to 16MPa to less than or equal to 33MPa, e.g., greater than or equal to 17MPa to less than or equal to 32MPa, greater than or equal to 18MPa to less than or equal to 31MPa, greater than or equal to 19MPa to less than or equal to 30MPa, greater than or equal to 20MPa to less than or equal to 29MPa, greater than or equal to 21MPa to less than or equal to 28MPa, greater than or equal to 22MPa to less than or equal to 27MPa, greater than or equal to 23MPa to less than or equal to 26MPa, greater than or equal to 24MPa to less than or equal to 25MPa, and all ranges and subranges formed between any of the foregoing endpoints. If the ratio a/t is too high, the warpage caused by the ion exchange treatment may be excessive. If the ratio A/t is too low, the fracture resistance of the glass-based article may be insufficient.

Stress profile of glass-based articles described hereinCan be given the ratio A/t^3/2Is characterized in that. In an embodiment, the ratio A/t^3/2Greater than or equal to 24MPa/mm^1/2E.g., greater than or equal to 26MPa/mm^1/227MPa/mm or more^1/2Greater than or equal to 28MPa/mm^1/2And 29MPa/mm or more^1/2Greater than or equal to 30MPa/mm^1/2And not less than 31MPa/mm^1/2Greater than or equal to 32MPa/mm^1/233MPa/mm or more^1/234MPa/mm or more^1/2Greater than or equal to 35MPa/mm^1/2Greater than or equal to 36MPa/mm^1/2Greater than or equal to 37MPa/mm^1/238MPa/mm or more^1/239MPa/mm or more^1/2Greater than or equal to 40MPa/mm^1/241MPa/mm or more^1/242MPa/mm or more^1/2Or more. In an embodiment, the ratio A/t^3/2Less than or equal to 43MPa/mm^1/2E.g. less than or equal to 42MPa/mm^1/241MPa/mm or less^1/2Less than or equal to 40MPa/mm^1/2Less than or equal to 29MPa/mm^1/238MPa/mm or less^1/2Less than or equal to 37MPa/mm^1/2Less than or equal to 36MPa/mm^1/2Less than or equal to 35MPa/mm^1/2Less than or equal to 34MPa/mm^1/233MPa/mm or less^1/2Less than or equal to 32MPa/mm^1/2Less than or equal to 31MPa/mm^1/2Less than or equal to 30MPa/mm^1/2Less than or equal to 29MPa/mm^1/2Less than or equal to 28MPa/mm^1/227MPa/mm or less^1/2Less than or equal to 26MPa/mm^1/2Less than or equal to 25MPa/mm^1/2Or smaller. In an embodiment, the ratio A/t^3/2Greater than or equal to 24MPa/mm^1/2To 43MPa/mm or less^1/2E.g., greater than or equal to 25MPa/mm^1/2To less than or equal to 42MPa/mm^1/226MPa/mm or more^1/2To 41MPa/mm or less^1/227MPa/mm or more^1/2To less than or equal to 40MPa/mm^1/2Greater than or equal to 28MPa/mm^1/2To less than or equal to 39MPa/mm^1/2And 29MPa/mm or more^1/2To 38MPa/mm or less^1/2And 30MPa/mm or more^1/2To less than or equal to 37MPa/mm^1/2And not less than 31MPa/mm^1/2To less than or equal to 36MPa/mm^1/2Greater than or equal to 32MPa/mm^1/2To 35MPa/mm or less^1/233MPa/mm or more^1/2To less than or equal to 34MPa/mm^1/2And all ranges and subranges formed between any of the foregoing endpoints.

The stress profile of the glass-based articles described herein may be characterized by a ratio a/(E × t), where E is the young's modulus of the glass-based substrate used to form the glass-based article. In an embodiment, the ratio a/(E × t) is greater than or equal to 3.5 × 10^-4E.g. greater than or equal to 4 × 10^-4Greater than or equal to 4.5X 10^-4Greater than or equal to 5X 10^-4Greater than or equal to 5.5X 10^-4Greater than or equal to 6X 10^-4Greater than or equal to 6.5X 10^-4Greater than or equal to 7X 10^-4Greater than or equal to 7.5X 10^-4Greater than or equal to 8 x 10^-4Greater than or equal to 8.5X 10^-4Or more. In an embodiment, the ratio a/(E × t) is less than or equal to 9 × 10^-4E.g. less than or equal to 8.5X 10^-4Less than or equal to 8X 10^-4Less than or equal to 7.5X 10^-4Less than or equal to 7X 10^-4Less than or equal to 6.5X 10^-4Less than or equal to 6X 10^-4Less than or equal to 5.5X 10^-4Less than or equal to 5X 10^-4Less than or equal to 4.5X 10^-4Less than or equal to 4X 10^-4Or smaller. In an embodiment, the ratio a/(E × t) ranges from greater than or equal to 3.5 × 10^-4To less than or equal to 9 x 10^-4E.g. greater than or equal to 4 × 10^-4To less than or equal to 8.5X 10^-4Greater than or equal to 4.5X 10^-4To less than or equal to 8 x 10^-4Greater than or equal to 5X 10^-4To less than or equal to 7.5X 10^-4Greater than or equal to 5.5X 10^-4To less than or equal to7×10^-4Greater than or equal to 6X 10^-4To less than or equal to 6.5X 10^-4And all ranges and subranges formed between any of the foregoing endpoints.

The stress profile of the glass-based articles described herein may have a ratio PT/(E × t) where E is the young's modulus of the glass-based substrate used to form the glass-based article. In an embodiment, the ratio PT/(E × t) is greater than or equal to 0.8m^-1E.g. greater than or equal to 0.9m^-11.0m or more^-11.1m or more^-11.2m or more^-11.3m or more^-11.4m or more^-1Greater than or equal to 1.5m^-11.6m or more^-11.7m or more^-11.8m or more^-1Greater than or equal to 1.9m^-1Greater than or equal to 2.0m^-1Greater than or equal to 2.1m^-1Or more. In an embodiment, the ratio PT/(E × t) is less than or equal to 2.2m^-1E.g. less than or equal to 2.1m^-1Less than or equal to 2.0m^-1Less than or equal to 1.9m^-1Less than or equal to 1.8m^-1Less than or equal to 1.7m^-1Less than or equal to 1.6m^-1Less than or equal to 1.5m^-1Less than or equal to 1.4m^-1Less than or equal to 1.3m^-1Less than or equal to 1.2m^-1Less than or equal to 1.1m^-1Less than or equal to 1.0m^-1Less than or equal to 0.9m^-1Or smaller. In an embodiment, the range of the ratio PT/(E × t) is greater than or equal to 0.8m^-1To less than or equal to 2.2mm^-1E.g. greater than or equal to 0.9m^-1To greater than or equal to 2.1m^-11.0m or more^-1To less than or equal to 2.0m^-11.1m or more^-1To less than or equal to 1.9m^-1Greater than or equal to 1.2m^-1To less than or equal to 1.8m^-11.3m or more^-1To less than or equal to 1.7m^-11.4m or more^-1To less than or equal to 1.6m^-1Greater than or equal to 1.5m^-1And the aforementioned terminalAll ranges and subranges formed between any one of them). If the ratio PT/(E × t) is too low, the fracture resistance of the glass-based article may be insufficient.

The glass-based article may have any suitable thickness. In one or more embodiments, the thickness (t) of the glass-based article is greater than or equal to 0.2mm to less than or equal to 2.0mm, e.g., greater than or equal to 0.3mm to less than or equal to 1.0mm, greater than or equal to 0.3mm to less than or equal to 0.8mm, greater than or equal to 0.4mm to less than or equal to 0.9mm, greater than or equal to 0.4mm to less than or equal to 0.6mm, greater than or equal to 0.5mm to less than or equal to 0.8mm, greater than or equal to 0.6mm to less than or equal to 0.7 mm). The thickness (t) may fall within a range formed between any of the foregoing values. The thickness of the glass-based article may be determined by the thickness of the glass-based substrate used to produce the glass-based article. In embodiments, the thickness of the glass-based article may be less than the thickness of the glass-based substrate used to form the glass-based article due to post-IOX processing (e.g., surface polishing or etching).

The glass-based articles described herein can exhibit high CS and reduced PT, while edge breakage can be advantageously limited.

The glass-based article may be characterized by any or all of the attributes and characteristics described herein. For example, stress profiles of the type described herein may be characterized by any combination of the attributes described herein.

Glass-based substrate

Examples of materials that may be used as the glass-based substrate may include alkali aluminosilicate glass compositions or alkali-containing aluminoborosilicate glass compositions, although other glass compositions are also contemplated. Specific examples of glass substrates that may be used include, but are not limited to, alkali aluminosilicate glasses, alkali containing borosilicate glasses, alkali aluminoborosilicate glasses, alkali containing lithium aluminosilicate glasses, or alkali containing phosphate glasses. The glass-based substrate has a base composition with ion-exchangeable features. As used herein, "ion-exchangeable" means that a substrate comprising the composition is capable of exchanging cations located at or near the surface of the substrate with cations of equivalent size that are larger or smaller. In embodiments, the glass-based substrate may comprise a lithium-containing aluminosilicate. In embodiments, the glass-based substrate may include an alkali-containing glass-ceramic.

In embodiments, the glass-based substrate may be formed from any composition capable of forming the stress profiles described herein. In embodiments, the glass-based substrate may be formed from a glass composition described in U.S. patent application publication No. 2019/0161390a1 entitled "Glasses With Low outside process Modifier Content," filed on 30/5/2019, the entire contents of which are incorporated herein by reference. In embodiments, the glass-based substrate may be formed from a glass composition described in U.S. patent application publication No. 2019/0161386a1 entitled "Ion-Exchangeable Mixed Alkali glass Glasses," filed on 30/5/2019, the entire contents of which are incorporated herein by reference.

The glass-based substrate may include Li₂And O. Including Li in a glass-based substrate₂O can increase the fracture toughness of the glass-based substrate and can reduce the time required to produce a desired stress profile by ion exchange. In an embodiment, Li of the glass-based substrate₂The molar concentration of O is less than or equal to 12 mol%.

In an embodiment, Li in the glass-based substrate₂O and Na₂The molar ratio of O is less than or equal to 2.0, e.g., less than or equal to 1.8, less than or equal to 1.7, less than or equal to 1.6, less than or equal to 1.5, less than or equal to 1.4, less than or equal to 1.3, less than or equal to 1.2, less than or equal to 1.1, less than or equal to 1.0, or less.

Glass-based substrates may be characterized by the manner in which they may be formed. For example, the glass-based substrate may be characterized as float formable (i.e., formed by a float process), down drawable, more particularly, fusion formable, or slot drawable (i.e., formed by a down draw process, such as a fusion draw process or a slot draw process).

Some embodiments of the glass-based substrates described herein may be formed by a downdraw process. The downdraw process produces a glass-based substrate having a uniform thickness relative to the pristine surface. Since the average flexural strength of the glass article is controlled by the number and size of the surface flaws, the pristine surface with minimal contact has a higher initial strength. In addition, the downdrawn glass articles have very flat and smooth surfaces that can be used in end applications without expensive grinding and polishing.

Some embodiments of the glass-based substrate may be described as being fusion formable (i.e., formable using a fusion draw process). The fusion process uses a draw tank having a channel for receiving molten glass feedstock. The channel has a weir that opens at the top along the length of the channel on both sides of the channel. As the channel is filled with molten material, the molten glass overflows the weir. Under the influence of gravity, the molten glass flows down the outer surface of the draw tank as two flowing glass films. The outer surfaces of these draw troughs extend downwardly and inwardly so that they meet at an edge below the draw trough. The two flowing glass films meet at the edge to fuse and form a single flowing glass article. The fusion draw process provides advantages because the two glass films overflowing to the channel fuse together so neither of the outer surfaces of the resulting glass article contacts any component of the apparatus. Thus, the surface properties of the fusion drawn glass article are not affected by such contact.

Some embodiments of the glass-based substrates described herein may be shaped by a slot draw process. The slot draw process is different from the fusion draw process. In the slot draw process, molten raw glass is supplied to a draw tank. The bottom of the draw tank has an open slot with a nozzle extending the length of the slot. The molten glass flows through the slot/nozzle and is drawn downward as a continuous glass article and into the annealing zone.

In some embodiments, the glass-based substrates described herein may be formed using a roll-forming process. For example, a roll forming process may be used to produce a glass-based substrate having a relatively uniform thickness.

In one or more embodiments, the glass-based substrates described herein may exhibit an amorphous microstructure and may be substantially free of crystals or crystallization. In other words, in some embodiments, the glass-based substrate article excludes a glass-ceramic material.

The glass-based substrate may have a 2-dimensional (2D), 2.5-dimensional (2.5D), or 3-dimensional (3D) shape. As used herein, a 2D shape refers to a glass-based substrate with both major surfaces flat (planar). As used herein, a 2.5D shape refers to a glass-based substrate where one major surface is flat (planar) and one major surface is curved. Common 2.5D shapes for glass-based articles include chamfered or chamfered edges. As used herein, a 3D shape refers to a glass-based substrate with both major surfaces curved.

Ion exchange (IOX) processing

Chemical strengthening of a glass-based substrate with a base composition is accomplished by contacting the glass-based substrate with an ion exchange source. Can be prepared by placing an ion-exchangeable glass-based substrate containing cations (e.g., K)⁺、Na⁺、Ag⁺Etc.) in a molten bath, wherein cations diffuse into the glass and the glass has smaller alkali ions (e.g., Na)⁺、Li⁺) Diffused into the molten bath. Replacing smaller cations with larger cations may create compressive stress near the top surface of the glass-based article. Tensile stresses are generated within the glass-based article to balance near-surface compressive stresses.

The IOX process used to form the glass-based articles described herein includes only a single ion exchange treatment. Such a process is known as single ion exchange (SIOX) processing. The use of the SIOX process may reduce cost and complexity as compared to multi-step ion exchange processing (e.g., an IOX process that includes processing in multiple molten baths).

The baths used to perform the ion exchange treatment on the glass-based substrates to form the glass-based articles disclosed herein may include a mixture of salts. In an embodiment, the IOX bath includes potassium and sodium. For example, the ion exchange bath may include a mixture of sodium nitrate and potassium nitrate, without including lithium nitrate. In other embodiments, the ion exchange bath may include a mixture of sodium nitrate, potassium nitrate, and lithium nitrate. The bath may also include silicic acid, for example, in an amount of about 0.5 wt% of the total amount of nitrates. In an embodiment, the IOX bath may include a carbonate salt, for example, potassium carbonate.

In an embodiment, the ion bath includes NaNO₃Less than or equal to 10 wt%, for example, less than or equal to 9.5 wt%, less than or equal to 9 wt%, less than or equal to 8.5 wt%, less than or equal to 8 wt%, less than or equal to 7.5 wt%, less than or equal to 7 wt%, less than or equal to 6.5 wt%, less than or equal to 6 wt%, less than or equal to 5.5 wt%, less than or equal to 5 wt%, less than or equal to 4.5 wt%, less than or equal to 3.5 wt%, less than or equal to 3 wt%, less than or equal to 2.5 wt%, less than or equal to 2 wt%, less than or equal to 1.5 wt%, or less. In an embodiment, the ion bath includes NaNO₃Greater than or equal to 1 wt%, for example, greater than or equal to 1.5 wt%, greater than or equal to 2 wt%, greater than or equal to 2.5 wt%, greater than or equal to 3 wt%, greater than or equal to 3.5 wt%, greater than or equal to 4 wt%, greater than or equal to 4.5 wt%, greater than or equal to 5 wt%, greater than or equal to 5.5 wt%, greater than or equal to 6 wt%, greater than or equal to 6.5 wt%, greater than or equal to 7 wt%, greater than or equal to 7.5 wt%, greater than or equal to 8 wt%, greater than or equal to 8.5 wt%, greater than or equal to 9 wt%, greater than or equal to 9.5 wt%, or greater. In an embodiment, the ion bath includes NaNO₃In the range of from greater than or equal to 1 wt% to less than or equal to 10 wt%, for example, from greater than or equal to 1.5 wt% to less than or equal to 9.5 wt%, from greater than or equal to 2 wt% to less than or equal to 9 wt%, from greater than or equal to 2.5 wt% to less than or equal to 8.5 wt%, from greater than or equal to 3.5 wt% to less than or equal to 7.5 wt%, from greater than or equal to 4 wt% to less than or equal to 7 wt%, from greater than or equal to 4.5 wt% to less than or equal to 4.5 wt% by weightGreater than or equal to 6.5 wt%, greater than or equal to 5.5 wt% to less than or equal to 6 wt%, greater than or equal to 4 wt% to less than or equal to 6 wt%, and all ranges and subranges formed between any of the foregoing endpoints. The balance of the IOX bath may be potassium, e.g., as KNO₃In the form of (a).

The IOX treatment, as defined by the time the glass-based substrate is in contact with the IOX medium, may be for any suitable period of time. In embodiments, the IOX treatment is for a period of time ranging from greater than or equal to 15 minutes to less than or equal to 200 minutes, e.g., greater than or equal to 20 minutes to less than or equal to 190 minutes, greater than or equal to 30 minutes to less than or equal to 180 minutes, greater than or equal to 40 minutes to less than or equal to 170 minutes, greater than or equal to 50 minutes to less than or equal to 160 minutes, greater than or equal to 60 minutes to less than or equal to 150 minutes, greater than or equal to 70 minutes to less than or equal to 140 minutes, greater than or equal to 80 minutes to less than or equal to 130 minutes, greater than or equal to 90 minutes to less than or equal to 120 minutes, greater than or equal to 100 minutes to less than or equal to 110 minutes, greater than or equal to 65 minutes to less than or equal to 180 minutes, and all ranges and subranges formed between any of the foregoing endpoints.

During the IOX treatment, the IOX bath may be at any suitable temperature. In embodiments, the temperature of the IOX bath ranges from greater than or equal to 370 ℃ to less than or equal to 450 ℃, e.g., from greater than or equal to 380 ℃ to less than or equal to 440 ℃, from greater than or equal to 390 ℃ to less than or equal to 430 ℃, from greater than or equal to 400 ℃ to less than or equal to 420 ℃, from greater than or equal to 410 ℃ to less than or equal to 450 ℃, from greater than or equal to 380 ℃ to less than or equal to 420 ℃, from greater than or equal to 380 ℃ to less than or equal to 390 ℃, and all ranges and subranges formed between any of the foregoing endpoints.

The IOX treatment described herein is characterized by the weight gain produced in the glass-based article. The weight gain was calculated as a percentage of the weight of the glass-based substrate prior to IOX treatment. In embodiments, the weight gain resulting from IOX treatment is less than or equal to 1%, e.g., less than or equal to 0.9%, less than or equal to 0.8%, less than or equal to 0.7%, less than or equal to 0.6%, less than or equal to 0.5%, less than or equal to 0.4%, less than or equal to 0.3%, less than or equal to 0.2%, less than or equal to 0.1%, or less.

After performing the ion exchange treatment, it is understood that the composition at the surface of the glass-based article is different from the composition of the as-formed glass-based substrate. This is due to one type of alkali metal ion (e.g., Li) in the as-formed glass⁺Or Na⁺) Are respectively coated with larger alkali metal ions (e.g. Na)⁺Or K⁺) And (6) replacing. However, in embodiments, the composition at or near the center of the depth of the glass-based article remains the same as the composition of the as-formed glass-based substrate.

End product

The glass-based articles disclosed herein may be bonded to another article, for example, an article having a display (or display article) (e.g., consumer electronics including cell phones, tablets, computers, navigation systems, and the like), an architectural article, a transportation article (e.g., vehicles, trains, aircraft, nautical devices, etc.), an appliance article, or any article that requires some transparency, scratch resistance, abrasion resistance, or a combination thereof). Fig. 3A and 3B illustrate exemplary articles incorporating any of the glass-based articles disclosed herein. Specifically, fig. 3A and 3B show a consumer electronic device 200 comprising: a housing 202, the housing 202 having a front surface 204, a rear surface 206, and side surfaces 208; electrical components (not shown) located at least partially inside the housing or completely inside the housing and including at least a controller, a memory, and a display 210 at or near the front surface of the housing; and an outer cover 212 at or above the front surface of the housing to cover the display. In an embodiment, at least a portion of at least one of the enclosure 212 and the housing 202 comprises any of the glass-based articles described herein.

Examples

The embodiments will be further clarified by the following examples. It is to be understood that these embodiments are not limited to the above-described embodiments.

Forming a glass-based substrate having the following exemplary composition: 63.70 mol% SiO₂16.18 mol% of Al₂O₃0.39 mol% of B₂O₃8.10 mol% of Na₂O, 0.53 mol% K₂O, 8.04 mol% Li₂O, 0.33 mol% MgO, 0.01 mol% TiO₂0.02 mol% of Fe₂O₃2.64 mol% of P₂O₅And 0.05 mol% of SnO₂。

Ion exchange is performed against the glass-based substrate. The ion exchange conditions as well as the measured properties are recorded in table I below. The ion exchange bath included the reported amount of sodium (e.g., sodium nitrate) along with 0.5 wt.% silicic acid, with the remainder being potassium nitrate. In table I, the sodium content of the ion exchange bath indicated by an "-" additionally comprises 5% by weight of K₂CO₃. The weight gain reported in table I was calculated by comparing the weight of the ion-exchanged glass-based article to the weight of the glass-based substrate used to form the glass-based article prior to the ion-exchange treatment. In some cases, the glass-based article broke during the ion exchange treatment, and weight gain could not be calculated.

TABLE I

Using 67.37 mol% SiO₂12.73 mol% of Al₂O₃3.67 mol% of B₂O₃13.77 mol% of Na₂O, 0.01 mol% of K₂O, 2.39 mol% MgO, 0.01 mol% ZrO₂0.01 mol% of Fe₂O₃And 0.09 mol% of SnO₂To prepare a comparative glass-based substrate.

The glass-based substrates having the above-described exemplary compositions were ion-exchanged with comparative glass-based substrates (each having a thickness of 0.4 mm). 4% by weight of NaNO at a temperature of 380 ℃ with respect to the glass-based substrate₃With 96% by weight of KNO₃Ion exchange was carried out for 65 minutes in the bath (1). KNO of 100 wt.% of a comparative glass-based substrate at a temperature of 420 ℃₃Ion exchange was carried out for 4 hours in the bath of (2). The stress profile of the resulting glass-based article was measured and is shown in fig. 4, where the comparative glass-based article is shown with a dashed line.

The first glass-based substrate, the second glass-based substrate, and the comparative glass-based substrate, each having a thickness of 0.6mm, were ion-exchanged. The first and second glass-based substrates have the above-described exemplary compositions. 4% by weight NaNO of the first glass-based substrate at a temperature of 380 ℃₃With 96% by weight of KNO₃Ion exchange was carried out for 65 minutes in the bath of (1). 4% by weight of NaNO at a temperature of 380 ℃ on a second glass-based substrate₃With 96% by weight of KNO₃Ion exchange was carried out for 75 minutes in the bath of (1). KNO of 100 wt.% of a comparative glass-based substrate at a temperature of 420 ℃₃Ion exchange was performed for 5.5 hours in the bath of (2). The stress profiles of the resulting glass-based articles were measured and are shown in fig. 5, where the first glass-based article is shown with solid lines, the second glass-based article is shown with dotted lines, and the comparative glass-based article is shown with dashed lines.

Examples 1, 2, and 3 below were produced from glass-based samples having the above-described exemplary compositions. The IOX bath contained 4 wt% NaNO₃About 96% by weight of KNO₃And 0.5% by weight of silicic acid, and the bath is at a temperature of 380 ℃. Table II reports the IOX time and the thickness of the glass-based substrate for each example.

TABLE II

TABLE II (continuation)

The measured properties reported in table II are the average of two measurements made in 90 ° different orientations. The retardation curve of example 2 is shown in fig. 6, where the horizontal axis is the position in the thickness direction of the glass-based article and the vertical axis is the retardation in radians. The surface of example 2 is located at about 0.05mm and 0.65mm on the graph of fig. 6. The limited portion of the delay curve is shown in fig. 7 and includes the minimum and maximum delays that occur at two DOC points in the glass-based article. The noise in the delay is successfully cancelled in fig. 7. A 6 th order polynomial fit is applied to this limited portion of the delay to take a smooth approximation for the delay around the minimum and maximum values and to calculate the minimum and maximum values more accurately. The delays shown in this fig. 7 are shown with dashed lines, while the fits are shown with solid lines. It will be appreciated that due to the limited resolution (limited size of the laser beam), the scattered light polarization method will typically slightly underestimate the difference between the minimum and maximum retardation when the thickness is less than about 1 mm. Thus, the estimate of the stress region proportional to the difference between the minimum and maximum delays represents a low end estimate, while the actual ratio a/(PT) may be slightly higher (typically not more than 5%).

The maximum slope can be found by fitting a derivative to the polynomial of fig. 7 and finding the maximum of the derivative polynomial. Alternatively, as shown in fig. 8, the maximum slope may be found by a linear fit to the central region (where the maximum slope occurs when the chemical strengthening of the sheet is substantially symmetric). In fig. 8, only the approximately linear portion of the center of the delay curve is retained for linear fitting.

All composition ingredients, relationships, and ratios described in this specification are provided in mole% unless otherwise indicated. All ranges disclosed in this specification are to be understood to encompass any and all ranges and subranges subsumed within the broad disclosed range, whether or not explicitly stated before or after the disclosed range.

It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Thus, it is intended that the present specification cover the modifications and variations of the various embodiments described herein provided they come within the scope of the appended claims and their equivalents.

Claims

1. A glass-based article, comprising:

a first surface and a second surface defining a thickness t, wherein t is greater than or equal to 0.2mm and less than or equal to 2.0 mm;

a peak tension PT of greater than or equal to 21 MPa;

a compressive stress CS of 650MPa or more and 1200MPa or less;

a peak depth of layer DOL of greater than or equal to 4.5 μm and less than or equal to 12.0 μm_SP(ii) a And

an inflection point compressive stress CS of 15MPa or more and 150MPa or less_K。

2. The glass-based article of claim 1, wherein the glass-based article is formed using a single ion exchange process.

3. The glass-based article of any one of claim 1 to the preceding claim, wherein PT is less than or equal to 80 MPa.

4. The glass-based article of any one of claims 1 to the preceding claim, wherein PT is greater than or equal to 43MPa and less than or equal to 78 MPa.

5. The glass-based article of any one of claims 1 to the preceding claim, wherein CS is greater than or equal to 800MPa and less than or equal to 1050 MPa.

6. The glass-based article of any one of claims 1 to the preceding claims, wherein DOL_SPGreater than or equal to 6.0 μm to 11.5 μm.

7. The glass-based article of any one of claims 1 to the preceding claims, wherein CS_KGreater than or equal to 30MPa and less than or equal to 125 MPa.

8. The glass-based article of any one of claims 1 to the preceding claims, wherein DOL_SPAnd/t is 0.010 or more and 0.030 or less.

9. The glass-based article of any one of claims 1 to the preceding claim, further comprising a depth of compression DOC, wherein DOC is greater than or equal to 0.11 t.

10. The glass-based article of any one of claims 1 to the preceding claim, further comprising a stress-depth integral, A, in the tensile stress region, and A/(PT) is greater than or equal to 0.4.

11. The glass-based article of any one of claims 1 to the preceding claim, further comprising a stress-depth integral, A, in the tensile stress region, and A/(PT) is less than or equal to 0.71.

12. The glass-based article of any one of claims 1 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stress region, and a/t is greater than or equal to 16 MPa.

13. The glass-based article of any one of claims 1 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stress region, and a/t is less than or equal to 22 MPa.

14. The glass-based article of any one of claims 1 to the preceding claim, further comprising a stress-depth integral a in the tensile stress region, and a/t^3/2Greater than or equal to 24MPa/mm^1/2。

15. The glass-based article of any one of claims 1 to the preceding claim, further comprising a stress-depth integral a in the tensile stress region, and a/t^3/2Less than or equal to 43MPa/mm^1/2。

16. The glass-based article of any one of claims 1 to the preceding claim, wherein PT/(Emt) is less than or equal to 2.2m^-1And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

17. The glass-based article of any one of claims 1 to the preceding claim, wherein PT/(E χ t) is greater than or equal to 0.8m^-1And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

18. The glass-based article of any one of claims 1 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stressed region, and a/(E τ) is less than or equal to 9 x 10^-4And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

19. The glass-based article of any one of claims 1 through the preceding claim, further comprising a stress-depth integral, a, in the tensile stressed region, and a/(E χ t) is greater than or equal to 3.5 x 10^-4And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

20. The glass-based article of any one of claim 1 to the preceding claim, wherein t is less than or equal to 0.65mm and PT is less than or equal to 60 MPa.

21. The glass-based article of any one of claims 1 to the preceding claims, wherein t is greater than or equal to 0.3mm and less than or equal to 0.8 mm.

22. The glass-based article of any one of claims 1 to the preceding claims, wherein t is greater than or equal to 0.4mm and less than or equal to 0.6 mm.

23. The glass-based article of any one of claims 1 through any one of the preceding claims, wherein Li at the center of the glass-based article₂Molar concentration of O and Na₂The ratio of the molar concentration of O is less than or equal to 2.0.

24. The glass-based article of any one of claims 1 to the preceding claims, wherein Li at the center of the glass-based article₂The O concentration is less than or equal to 12 mol%.

25. A glass-based article, comprising:

a peak tension PT of greater than or equal to 21 MPa;

a compressive stress CS of 650MPa or more and 1200MPa or less;

peak depth of layer DOL_SPWherein DOL_SPT is greater than or equal to 0.007 and less than or equal to 0.030; and

26. The glass-based article of claim 25, wherein the glass-based article is formed using a single ion exchange process.

27. The glass-based article of any one of claims 25 to the preceding claim, wherein PT is less than or equal to 80 MPa.

28. The glass-based article of any one of claims 25 to the preceding claim, wherein PT is greater than or equal to 43MPa and less than or equal to 78 MPa.

29. The glass-based article of any one of claims 25 through the preceding claim, wherein CS is greater than or equal to 800MPa and less than or equal to 1050 MPa.

30. The glass-based article of any one of claims 25 to the preceding claims, wherein DOL_SPGreater than or equal to 6.0 μm and less than or equal to 11.5. mu.m.

31. The glass-based article of any one of claims 25 to the preceding claim, wherein CS_KGreater than or equal to 30MPa and less than or equal to 125 MPa.

32. The glass-based article of any one of claims 25 to the preceding claims, wherein DOL_SPThe/t is 0.010 or more and 0.029 or less.

33. The glass-based article of any one of claims 25 to the preceding claim, further comprising a depth of compression DOC, wherein DOC is greater than or equal to 0.11 t.

34. The glass-based article of any one of claims 25 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stress region, and a/(PT) is greater than or equal to 0.4.

35. The glass-based article of any one of claims 25 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stress region, and a/(PT) is less than or equal to 0.71.

36. The glass-based article of any one of claims 25 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stress region, and a/t is greater than or equal to 16 MPa.

37. The glass-based article of any one of claims 25 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stress region, and a/t is less than or equal to 22 MPa.

38. The glass-based article of any one of claims 25 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stress region, and a/t^3/2Greater than or equal to 24MPa/mm^1/2。

39. The glass-based article of any one of claims 25 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stress region, and a/t^3/2Less than or equal to 43MPa/mm^1/2。

40. The glass-based article of any one of claims 25 to the preceding claim, wherein PT/(E t) is less than or equal to 2.2m^-1And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

41. The glass-based article of any one of claims 25 to the preceding claim, wherein PT/(E χ t) is greater than or equal to 0.8m^-1And E is the young's modulus of a glass-based substrate having the same composition and microstructure as the center of the glass-based article.

42. The glass-based article of any one of claims 25 to the preceding claim, further comprising a stress-depth integral, a, in the tensile stressed region, and a/(E τ) is less than or equal to 9 x 10^-4And E is the Young's modulus of a glass-based substrate having the same composition and microstructure as the center of the glass-based article.

43. A glass as claimed in any one of claims 25 to preceding claimsA glass-based article further comprising a stress-depth integral a in the tensile stressed region, and a/(E t) is greater than or equal to 3.5 x 10^-4And E is the young's modulus of the glass-based substrate having the same composition and microstructure as the center of the glass-based article.

44. The glass-based article of any one of claims 25 to the preceding claims, wherein t is less than or equal to 0.65mm and PT is less than or equal to 60 MPa.

45. The glass-based article of any one of claims 25 to the preceding claim, wherein t is greater than or equal to 0.3mm and less than or equal to 0.8 mm.

46. The glass-based article of any one of claims 25 to the preceding claim, wherein t is greater than or equal to 0.4mm and less than or equal to 0.6 mm.

47. The glass-based article of any one of claims 25 to the preceding claim, wherein Li at the center of the glass-based article₂Molar concentration of O and Na₂The ratio of the molar concentration of O is less than or equal to 2.0.

48. The glass-based article of any one of claims 25 to the preceding claim, wherein Li at the center of the glass-based article₂The O concentration is less than or equal to 12 mol%.

49. A consumer electronic product, the consumer electronic product comprising:

a housing comprising a front surface, a rear surface, and side surfaces;

an electrical component disposed at least partially within the housing, the electrical component including at least a controller, a memory, and a display, the display disposed at or adjacent to a front surface of the housing; and

a housing disposed over the display;

wherein at least a portion of at least one of the housing and the enclosure comprises the glass-based article of any one of the preceding claims.

50. A method, the method comprising:

exposing the glass-based substrate to an ion exchange bath to form a glass-based article;

wherein:

the glass-based substrate comprises a first surface and a second surface defining a thickness t, wherein t is greater than or equal to 0.2mm and less than or equal to 2.0 mm;

the glass-based article comprises:

a peak tension PT of greater than or equal to 21 MPa;

a compressive stress CS of 650MPa or more and 1200MPa or less;

an inflection point compressive stress CS of 15MPa or more and 150MPa or less_K(ii) a And the ion exchange bath comprises potassium and sodium.

51. A method, the method comprising:

wherein:

the glass-based substrate comprises: a first surface and a second surface defining a thickness t, wherein t is greater than or equal to 0.2mm to less than or equal to 2.0 mm;

the glass-based article comprises:

a peak tension PT of greater than or equal to 21 MPa;

a compressive stress CS of 650MPa or more and 1200MPa or less;

peak depth of layer DOL_SPIn which DOL_SPThe/t is greater than or equal to 0.007 and less than or equal to 0.030; and

52. The method of any one of claims 50 to the preceding claims, wherein the method does not comprise any additional ion exchange treatment.

53. The method of any one of claims 50 to the preceding claims, wherein the temperature of the ion exchange bath is greater than or equal to 370 ℃ and less than or equal to 450 ℃.

54. The method of any one of claims 50 to the preceding claims, wherein the temperature of the ion exchange bath is greater than or equal to 380 ℃ and less than or equal to 420 ℃.

55. The method of any one of claims 50 to the preceding claims, wherein the temperature of the ion exchange bath is greater than or equal to 380 ℃ and less than or equal to 390 ℃.

56. The method of any one of claims 50 to the preceding claims, wherein the ion exchange bath comprises NaNO₃The amount of (b) is greater than or equal to 1 wt% and less than or equal to 10 wt%.

57. The method of any one of claims 50 to the preceding claims, wherein the ion exchange bath comprises NaNO₃The amount of (b) is greater than or equal to 4 wt% and less than or equal to 9 wt%.

58. The method of any one of claims 50 to the preceding claims, wherein the exposing is for a time greater than or equal to 15 minutes and less than or equal to 200 minutes.

59. The method of any one of claims 50 to the preceding claims, wherein the exposing is for a time greater than or equal to 65 minutes and less than or equal to 180 minutes.

60. The method of any one of claims 50 through the preceding claims, wherein the glass-based substrateLi being contained₂Molar concentration of O and Na₂The ratio of the molar concentration of O is less than or equal to 2.0.

61. The method of any one of claims 50 through the preceding claims, wherein the glass-based substrate comprises Li₂The O concentration is less than or equal to 12 mol%.

62. The method of any one of claims 50-preceding claim, wherein the glass-based article has a weight gain of less than or equal to 1% as compared to the glass-based substrate.